\version "2.6.0"

\header {

    texidoc = "A volta repeat may begin with a grace. Consecutive
    ending and starting repeat bars are merged into one @code{:||:}."

      }

    \layout { raggedright= ##t }

\score {\relative c' {
\repeat volta 2 {
        c1 
}
\repeat volta 2 {
        \grace {c8 } c4
}
}}
